Fullerenes Enhance Self-Assembly and Electron Injection of Photosystem I in Biophotovoltaic Devices

Abstract

This paper describes the fabrication of microfluidic devices with a focus on controlling the orientation of photosystem I (PSI) complexes, which directly affects the performance of biophotovoltaic devices by maximizing the efficiency of the extraction of electron/hole pairs from the complexes. The surface chemistry of the electrode on which the complexes assemble plays a critical role in their orientation. We compared the degree of orientation on self-assembled monolayers of phenyl-C 61 -butyric acid and a custom peptide on nanostructured gold electrodes. Biophotovoltaic devices fabricated with the C 61 fulleroid exhibit significantly improved performance and reproducibility compared to those utilizing the peptide, yielding a 1.6-fold increase in efficiency. In addition, the C 61 -based devices were more stable under continuous illumination. Our findings show that fulleroids, which are well-known acceptor materials in organic photovoltaic devices, facilitate the extraction of electrons from PSI complexes without sacrificing control over the orientation of the complexes, highlighting this combination of traditional organic semiconductors with biomolecules as a viable approach to coopting natural photosynthetic systems for use in solar cells.

Printable logic circuits comprising self-assembled protein complexes

“…23, CP-AFM junctions comprise individual PSI complexes, 98% of which rectified, indicating near-perfect unidirectional orientation (a detailed discussion on the determination of PSI orientation is provided in Supporting Information) 15,20,21 . This is further corroborated by the enhanced power conversion efficiency and short-circuit current of dye-sensitized solar cells comprising SAMs of PSI on PCBA, in which the optimized orientation of PSI improves the alignment of charge-transport chain to mitigate the recombination of excitons 28 . The voltage dependence of R in Fig.…”

Protein Orientation Defines Rectification of Electronic Current via Solid-State Junction of Entire Photosystem-1 Complex

“…This indicates that linkers with different head groups can be used for controlling the binding orientation of the PS1 complex, relative to the Au substrate (for the distribution of charges on the surface of the PS1 at different pH see Figure S2). Different linkers have been previously used to selectively orient PS1 complexes on a Au substrate. ,,, Here we have employed four different linkers, i.e., mercaptopropanoic acid (MPA) with −COOH/COO – end groups that can interact by electrostatic and hydrogen bonds, 2-mercaptoethanol (ME) with −OH end groups that can form hydrogen bonds with PS1, 3-mercapto-1-propanesulfonic acid (MPS) with a negatively charged sulfonate group, and 6-amino-1-hexanethiol (AH) linker with a positive linker headgroup which can interact with different surface parts of the entire protein PS1 complex (for the electrostatic charge distribution on the surface of PS1 at pH 7.5 see Figure A).…”

Molecular Electronics: Creating and Bridging Molecular Junctions and Promoting Its Commercialization

“…As a complementary configuration, a large-area molecular junction comprising an ensemble of molecules (via self-assembly, [56] Langmuir-Blodgett, [57] or other methods) allows the massive fabrication of high-quality and reproducible molecular electronic devices; therefore, they are much more appealing for industrial processes. [58] Additionally, the collective effects in ensemble molecular junctions, such as intermolecular interactions induced by the close packing of the molecules [59,60] and energy alignment across the electrodemolecule interfaces, [61,62] may influence the electrical behavior of these systems, thereby increasing the degree of freedom to manipulate the performance of molecular devices. Both singlemolecule and ensemble molecular junctions have their own scientific significances, and together build the fascinating world of molecular electronics.…”